If you are a GCC resident: you can travel using Visa Type 29A (GCC Resident Tourist Visa) if you’re the main traveler with an approved profession, or Visa Type 29B if you’re the companion of the main traveler.
If you don’t have a residency in GCC, then you’ll have to apply for the Dubai Oman Common Visa through one of Oman’s embassy offices or via tourist travel agencies and can enter through the airport or through the Hatta Border, and Visa duration has to be valid for at least 21 days pre-entry to Oman.